Cluster tools are well-known in the prior art. FIG. 1 is a simplified diagram of a cluster tool 100, as disclosed in U.S. Pat. No. 6,321,134, whose contents are incorporated by references. The prior art cluster tool 100 is configured in a circular or round annular configuration. More particularly, as seen in this figure, the cluster tool 100 takes on a hexagonal configuration with six facets. That is, transfer chamber 102, including a robot 104, is placed in a center region, which is surrounded by a plurality of vacuum processing chambers, shown by at least reference numerals 106A, 106B, 106C, 106D, and 106E. It is understood that the transfer chamber 102 is provided with a vacuum pump, or the like, as are the process chambers.
Connected to the transfer chamber 102 is a load lock 116 that may be ported to a clean room where the wafers are stored. As is known to those skilled in the art, robot 104 typically has a hinged arm terminating in a wafer handle 110 for holding a wafer 108. The wafer handle may be disk-shaped, prong-shaped or take on some other shape. Robot 104 can insert and remove a wafer 108 or wafers from any one of the chambers 106A-106E, or into the load lock 116, according to a desired application.
FIG. 2 shows another prior art cluster tool 200 which is arranged an in-line or linear configuration. That is, transfer chamber 202, including a robot 204, is placed in parallel alignment with a plurality of vacuum process chambers, shown by reference numerals 206A, 206B, 206C, 206D, 206E and 206F. It is again understood that the transfer chamber 202 is provided with a vacuum pump, or the like, as are the process chambers. A load lock 216 is also provided. Robot 204 can insert and remove a wafer 208 or wafers, which rests on wafer handler 210, from any one of the chambers 206A-206F, or into the load lock 116, according to a desired application.
The individual chambers in either prior art cluster tool 100 or 200 may be provisioned with necessary chucks, tools, valves, connections, and the like, to effect one or more processing steps, all under the direction of one or more controllers, as known to those skilled in the art. It is further understood that a variety of pumps, gas cylinder, ion sources, and the like, may be housed within, and/or connected to the various chambers.
As also known to those skilled in the art, the prior art cluster tools 100, 200 are typically coupled to a controller. Such a controller includes a variety of elements such as a microprocessor based unit, a hard disk memory storage unit, input/output elements such as a pointer device (e.g., mouse), a keyboard and/or touch screen, mouse, and other elements. The controller also may also be associated with a display such as a flat panel display, cathode ray tube (“CRT”), and the like. The display has a graphical user interface that includes a menu. The menu or menus can correspond to a variety of process recipes that are stored on the hard drive or other memory device. The process recipes can be in the form of a computer program or programs that use computer codes in the form of software. The computer codes carryout the functionality described herein as well as others. A network interface may also be provided.
As disclosed in U.S. Pat. No. 6,763,840, whose contents are also incorporated by reference, supercritical CO2 may be used to clean a substrate in a pressure chamber of a cluster tool. For this, the substrate is first placed in a pressure chamber and the chamber is then pressurized. Next, CO2 is introduced into the pressure chamber, and the substrate is cleaned with the CO2. The CO2 is next removed from the pressure chamber, and the pressure chamber is depressurized. Finally, the substrate itself is removed from the chamber.